I've only been to Flight Safety in TUS so I have nothing to compare other training centers. I've always had a positive experience in their 45 program. I think my last recurrent was #5 or #6.
I'll echo what Zap said. It's a great airplane, no real gotchas that I can think of. If it was a bit bigger it would be a perfect airplane (which is why I want the boss to get a CL300, it's just a larger 45). As mentioned before when I give a pax brief, I let them know the bathroom is a "sit down affair". They all laugh, but then thank me for the tip if it's been a long leg and a couple beers were involved. It does tend to be front heavy (forward CG) so be carefull for that. You have to get creative if you want to load 8 pax that didn't bring very much baggage. Like a long day trip. If you have 8-180lbs pax you can take 5500lbs of fuel and need 200lbs of ballast in the tail. That puts you right at gross and at the forward take off CG limit. Landing won't be an issue, as once fuel is burned and you lighten up the CG range widens. Speaking of baggage, practice some Tetris. If you get good at packing it can hold a lot of stuff. It's a million times better than dragging bags through the interior of an old 20/30 series Lear.
If you've got any other questions at all feel free to pm. Good luck and have fun. If you go to Baggins, get the "cowboy", best. sandwich. ever.