I was given a Genesis React Pro I think? Was in a dive shops junk bin, definitely wouldn't recommend, GUI wasn't bad, computer worked very well, but wouldn't recommend a computer that doesn't do decompression. It does have gauge mode though which puts it above the Zoop and some other recreational computer. Any computer without Gauge mode is not worth even considering. I've put many hours on Zoops to have the same profile as students I was working with and it is an abysmal computer
Next was a Cressi Archimede II which is the same as the Nitek Duo, Apeks Quantum, Tusa IQ and a slew of others made by Seiko. Was a wonderful little computer and took me through full cave training. Still recommend people one of those used since you can grab them for $100 or so, gets mixed gas/deco and can be used in gauge mode. Only downfall is you have to hit the backlight to get it to be seen in the dark. Not a huge deal, but something to consider. There's a Nitek Duo on ebay with bungee mount for $100 right now, killer deal for anyone looking.
Using a Petrel now.
Recommendation would be as follows for new divers
Avoid consoles, avoid anything without Gauge mode, avoid anything without decompression/2 gas, avoid AI. Make sure it hits the first two minimu and there is no diving you could do that would render that computer a paperweight. If it does the first three, wrist mount, and gauge mode, with 2 gas decompression, it will do 98% of the dives being done throughout the world including most technical diving. 2 gas deco is most of what is being done, and in gauge mode you can use it as a sanity check for trimix/CCR diving.
If you are doing a lot of travel diving, then I would recommend a true watch style computer that hits the above criteria. Going to be a bit more expensive than some of the larger "puck styles" and potentially a bit harder to read if you need cheaters to read a normal watch, but when you're travelling it allows you to keep the easiest piece of gear to have stolen on your body through the whole trip. Oceanic Geo 2.0 would fit quite nicely into this category. The old Nitek Plus was great as well, but has been discontinued for a while now