2: It's all fuzzy. Don't expect to ask for something in the prompt
and hear it immediately; sometimes it happens but quite often it
needs a few generations, so don't give up and be prepared to
a nice surprise after multiple retries.
This applies to everything, lyrics included; sometimes it sings
the wrong parts, mixed up lines, words, or doesn't sing them at
all, and sometimes it blends up words in strange new languages;
that is also part of the fun, but can cost money.

2b: Hallucinations. They happen in the above form, or as bad
sound quality (see below). If words are misspelled they can
be corrected by the replace section function, however if as
a result of hallucination say it sang a verse twice, deleting
the unwanted one becomes hard because the AI now lost sync between
music and lyrics, and when you attempt to correct that part it
could operate at the wrong position. In such eventuality it's
probably quicker and cheaper to extend the song from a point
before the hallucination, so that everything onwards is
overwritten, including the hallucination. Luckily however the
function to replace a part costs credits only after confirming
it, therefore one can retry indefinitely at no cost until the
correct piece is generated then confirmed.

3: Sound quality - This varies from quite good to really nasty,
and so far there's almost nothing that can be done to correct a
bad sounding track or section : sometimes a song is heavily
distorted (digital distortion, not like simple clipping), and
quite often making a cover will generate another bad sounding
track. Substituting sections doesn't always work.
Another very annoying bug is the tendency to raise the volume
of vocals and music with time, and that has nothing to do with
different emphasis or changing anything in the way it sings, it
just becomes louder and louder with time, usually after the 1st
minute. If that happens (more often with some genres) again,
here's nothing that can be done except making a cover and hoping.
This is my #1 annoyance with Suno; pretty much 70% of my songs
sound like crap because of that, although most of them start
very clean, but then slowly become louder and louder; one can
easily spot the problem just by looking at their wave plots.

4: User control - User can enter their lyrics or ask the AI to
generate them itself based on the user prompt, and results vary
from decent to sometimes surprisingly good. Also with original
lyrics it's amazing how it finds the best way to fit them into
a song, and I don't even write in English. Simply astounding!
Control over song creation is quite limited however; one can
give directions but chords insertion is limited to things
like [G#m] before the affected line, and I think very basic
rhythm figures can be entered in some way, but I still didn't
test those features. A xoxoxo grid to enter rhythms would be a
killer feature, but please, dear Suno engineers, don't assume
everyone wants to make a 4/4 hip hop figure on a 16 step grid;
my favorite drummer is Neil Peart and... yes, one can totally
program YYZ-like things on a capable enough drum machine.

Personas are a very recent addition; once the user creates
a song whose style (+instruments and vocals) they like, the
personas function can be used to create a virtual artist that
inherits those characteristics, so that following songs created
using the same persona will be similar in style and sound.
Be warned however that they seem to inherit low quality
hallucinations as well.
I've thrown away lots of credits wondering why a persona I created
made great songs that I liked a lot, but all of them, and i mean
really all of them, sounded like dog crap. If you get a bad song
don't make a persona out of it as it probably won't be worth the
effort, but keep it just in case they correct the AI so that
it can be used to correct bad sounding songs and personas.

4b: Users songs, along with all pieces created to correct
them, are thrown into a giant library that grows and grows, and
finding an old song can be frustrating for lacking any mechanism
to search them in unique way, just by title, style or lyrics,
which helps but it's far from perfect. Being able to tag songs
with a number (for example a ANSI timestamp) and having related
pieces grouped under thir own subdirectory would help a lot.
My library grew to over 200 pages, and I deleted a lot of stuff
before giving up. It was just so time consuming.
Playlists could help in this context, although that wouldn't be
their intended use.

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