In summary, my advice is to buy high quality surge protection. The dual protection is better because of the built in ground to shunt away the surges. Surge protection is sort of a pay me now, or pay me later situation. Surge protectors and UPSs are rated in joules and I recommend a rating of 90. Lesser ratings will still protect your equipment, but will often destroy themselves when hit by a surge if their rating is exceeded, and will require replacement.
Surge protectors are mainly for upward surges and spikes.
UPS devices can handle both upward and downward voltages, but are not quite as good at surge protection. In spite of everything I have described above, absolutely nothing will protect you in the event of a direct lightning hit. One other thing to keep in mind is that the metal oxide varistor devices in most surge protectors do wear out and it s wise to replace a surge protector about every four years. If the many choices of surge protection confuse you, seek a knowledgeable person in your user group for advice. Don t depend on the store s salesperson.