Having not handled one, I can only give an impression:
Cressi equipment is generally good, can be pricey. Their Comanche model is a bit plasticky but a fantastic value and a modern classic and parts are/were more readily available that most and reasonably priced.
[ame=http://www.youtube.com/watch?v=3TXPYCbVJ8s]Cressi Geronimo 2 Speargun - YouTube[/ame]
Looks nice. Handle looks neat - if the handle is raked back too much it might cause wrist strain for closer shots. Normal sort of eurogun (which is good). He mentions a spear guide on top - sounds like a rail but I think they would make more of that if it was a full rail - you don't need a rail on a 75cm gun (maybe handy on a 100/110cm+) but certainly does no harm & nice to have I guess, especially if you change wishbone/band configuration. Looks like the front of the bands might be mounted to a metal "wishbone" at the muzzle - if so thats probably good/strong but if it pivots (like my Omer XXV's) I wouldn't recommend it for beginners but it appears fixed to me. Not sure about the trigger tension feature, seems unnecessary (I prefer the sound of the Omer Cayman's constant trigger tension feature - but shotguns & airguns sometimes have trigger tension settings) and we generally recommend that you
do not use safety catch features (only slack bands are safe); spearos will often remove or permanently disable (un)"safety"-catches, to avoid unnecessarily losing fish if the catch is accidently set.
I'd be happy to get/use one (provided it is reasonably priced of course). It looks nice and light and streamlined - functional. I would probably want to do something about that safety catch. Sharp edged metal wishbones are still standard on euro-guns, I prefer soft Dyneema wishbones (safer, quieter, cheaper) - however the metal ones can last decades (Dyneema ones 1-3 years typically in my experience) and I suspect they *might* offer better accuracy/consistency on a eurogun designed to use them. Watch you fingers though

Also, spearos tend to prefer and stick with whatever wishbone-type they started with.
As you already have a Cressi (with a similar handle/mech too), which presumably you like as you are considering another Cressi, you will probably get on fine with it.
As you already have a short close-in speargun - I guess as alternative you might consider a longer gun, e.g. 80/90cm. For the UK though, I find the 75cm size most versatile (or perhaps an RA70). Others swear by 90cm, perhaps for Cornwall/Pembroke/Channel islands, which can have very clear conditions but the visibility & currents I have experienced most suggests the smaller gun. Also, I find in very clear conditions that 90cm is often not enough (the fish can see you & stay further away). I currently have 75cm & 90cm spearguns and always use the 75cm (having started with a 90). I now wonder if a better "pair" might be 75cm for general use & 110cm (+/-10cm) for exceptionally clear conditions - which come to think of it is probably not unlike what a lot of Mediterranean spearos, like Spaghetti, would use.
I don't think the model/features are that critical for a smaller gun like a 75cm - although I am incredibly pleased my Omer XXV 75, which has a slim 25mm carbon barrel & versatile muzzle configurations (which can be a pain but will eventually be converted to nice, cheap, simple, powerful bulk rubber) and I've converted it to Dyneema wishbone. However I have also heard of folk that love their 75 Comanches.
Perhaps you could review the Cressi Geronimo Crevasse 45 for us - it might also help you see what you like/dislike about Cressi designs & what you might be looking for in your next speargun.