Question: Have musicians Hansi Kürsch and John Reis both performed as members of a band?

Context paragraphs:
André Olbrich: André Olbrich (born 3 May 1967, in Düsseldorf, Germany) is a German guitarist, composer and backing vocalist, most known as the co-founder and lead guitarist of power metal band Blind Guardian, in which he serves as one of the main composers with other co-founder Hansi Kürsch.

Jon Schaffer: Jon Ryan Schaffer (born March 15, 1968) is an American heavy metal musician.  He is best known as the guitarist and last remaining original member of the Florida-based heavy metal band Iced Earth, which he formed in 1985 under the name "Purgatory".  He also sings in his side project Sons of Liberty and played guitar for Demons and Wizards, his collaboration with Blind Guardian frontman Hansi Kürsch.

Ghost Ship (album): Ghost Ship is the first album by the San Diego, California, rock and roll band Sultans, released in 2000 by Swami Records.  Both the band and the album began as "side projects" for John Reis during time off from his main band, Rocket from the Crypt.  This was also the time at which Reis formed Hot Snakes.  Reis collaborated with drummer Tony Di Prima, bringing in Rocket From the Crypt guitarist Andy Stamets while Reis himself played the bass guitar (he is normally known as a guitarist).  The band chose the name Sultans for the project and recorded an introductory EP and "Ghost Ship", both of which were released that year on Reis' newly formed Swami label.  As Reis has a tradition of using different stage names or pseudonyms in his various projects, he chose to be known as "Slasher" in the Sultans, while Stamets chose the nickname "Black Flame".

Hansi Kürsch: Hans Jürgen Kürsch, better known as Hansi Kürsch (born 10 August 1966 in Lank-Latum/Meerbusch, Germany), is a German musician best known for being the co-founder, lead vocalist, co-composer, and lyricist of power metal band Blind Guardian.  He was also the bassist in Blind Guardian until the 1998 album "Nightfall in Middle-Earth".  He also provides lead vocals for the band Demons and Wizards.

John Reis: John Reis (born 1969) and also known by the pseudonyms Speedo, Slasher, and The Swami is an American musician, singer, guitarist, record label owner, and disc jockey.  He is best known as the singer and guitarist for the rock band Rocket from the Crypt, which he formed and fronted (as Speedo) for the entirety of its career from 1990 to 2005.  Prior to this he was the guitarist in the post-hardcore band Pitchfork, and also played in Drive Like Jehu during the early 1990s.  In 1999 he formed the Hot Snakes, and in 2000 also formed the Sultans, in which (as Slasher) he sang and originally played bass before switching to rhythm guitar.  He played in both these bands until their breakups in 2005 and 2007 respectively.  He also released a solo recording under the name Back Off Cupids, which was recorded in 1994 but not released until 1999.  Over the years he has performed in many other musical acts including Conservative Itch, Stacatto Reads, Custom Floor, and Beehive & the Barracudas.  He is the owner of Swami Records, a label he founded in 1999 (he uses the title The Swami in this capacity).  He frequently works with bands in a studio capacity and releases albums by many southern California groups through his label.  He also hosts the "Swami Sound System" program (previously on San Diego radio station 94.9 (KBZT), and now available on Slacker Radio).  Reis remains an influential figure in the San Diego underground music community and is currently performing with a new band named The Night Marchers.

Vain Glory Opera: Vain Glory Opera is the third (or second "official") studio album by the German power metal band Edguy, released in 1998.  It was mixed by Stratovarius' Timo Tolkki, who also played additional lead guitar on "Out Of Control", and featured additional lead and backing vocals by Hansi Kürsch of Blind Guardian on "Out of Control" and the title track "Vain Glory Opera."  Further choir vocals were supplied by Ralf Zdiarstek and Norman Meiritz.  At the time of recording the album, Edguy had not yet chosen a permanent drummer to succeed Dominik Storch.  So session musician Frank Lindenthal, a good friend of the band, was asked to play drums on the album.

See You in Magic: See You in Magic is the debut album by the San Diego, California rock band The Night Marchers, released in 2008 by Vagrant Records and Swami Records.  The Night Marchers are the latest musical project of singer/guitarist John Reis, previously of Pitchfork, Drive Like Jehu, Rocket from the Crypt, the Hot Snakes, and the Sultans.  Reis announced the group's formation in August 2007, after all of his previous acts had broken up by January of that year.  The band also includes Beehive and the Barracudas guitarist Gar Wood, CPC Gangbangs bassist Tommy Kitsos, and former Delta 72 drummer Jason Kourkounis.  Wood and Kourkounis had previously recorded and performed with Reis in the Hot Snakes.  The band members are credited on the album using pseudonyms that they had used in their previous acts: Reis is credited as "Speedo" (his stage name in Rocket from the Crypt), Wood as "Dner" (Beehive and the Barracudas), Kitsos as "Skitsos" (CPC Gangbangs), and Kourkounis as "Jsinclair" (Hot Snakes).

Blind Guardian: Blind Guardian is a German power metal band formed in the mid-1980s in Krefeld, West Germany.  They are often credited as one of the seminal and most influential bands in the power metal and speed metal subgenres.  Ten musicians have been a part of the band's line-up in its history, which has consisted of singer Hansi Kürsch, guitarists André Olbrich and Marcus Siepen, and drummer Frederik Ehmke since 2005.

Demons and Wizards (band): Demons and Wizards is a power metal band conceived as a side-project by vocalist for Blind Guardian, Hansi Kürsch, and the guitarist for Iced Earth, Jon Schaffer.  Schaffer writes the music and Kürsch writes the lyrics.  The band's line-up during the recording of their first album in 1999 also featured Mark Prator, who was the drummer on a few Iced Earth albums, and Jim Morris doing most of the guitar solos, Morris also having worked with Iced Earth in the past.

Reversing Time: Reversing Time is the first studio album of the Greek - Turkish band Dreamtone & Iris Mavraki's Neverland, released in February 2008.  Hansi Kürsch (Blind Guardian) and Tom S. Englund (Evergrey) participated in this project.

Supporting paragraphs: Hansi Kürsch John Reis
Answer: yes