The first question to ask yourself is what Division you want to shoot in?
Revolver Division is for, you guessed it revolvers. The competitive gun in revolver division is a S&W 625 in .45ACP with moon clips for fast reloads.
Standard Division is dominated by double stack 1911s in .40 S&W. You can also compete with a .45. 9mm is not an option in Standard if you want to be competitive, as it is scored minor which is a handicap against the .40 & .45 which are scored major. Basically, unless you can hit the A zone every time, forget about 9mm in Standard.
In Canada you can compete with a single stack gun, but they aren't as fast on the reloads as the double stacks.
The three main options are the STI, the Bul M5 from Marstar & the Para Ordnance P16-40. The STI & the Bul should be fine out of the box, the Para will need parts replacement over time.
Another option is a single action Tanfoglio, these used to have a bad reputation but they have been building some very nice guns in the last few years.
Production division is for double action or striker fired guns. There is an approved list of guns to choose from at
www.ipsc.org
Production Division is only scored minor, so 9mm firearms rule as they have less recoil than .40 or .45 with factory ammo. If you are going to reload then the other calibres become an option. There are a lot of guns to choose from, at the moment the ones that available in canada and that seem to be competitive in the right hands are as follows:
CZ SP01 is the flavour of the moment. there are a lot of factory options available for it, including a .22 conversion unit.
Glock 17 is still competitive, at a recent state titles here in Australia, seven out of the top 10 Production shooters had Glocks. The Glock comes with crappy sights, so factor in buying Heine straight eights or a similar aftermarket sight from the start.
S&W M&P is very Glock like, with good sights and interchangable backstraps to adjust the grip. It's flavour of the month with the plastic pistol fans, mainly because it's new and relatively cheap.
Springfield Armoury XD, again a very Glock like gun, with better sights and a more natural grip. Spare parts are hard to get in Canada. Look at the tactical model with a longer site radius.
Beretta 90-two is the replacement for several Beretta models. Although beloved of many fans, myself included, Berettas just don't seem to be competitive in IPSC for most shooters. The trigger is a lot harder to master. Beretta are discontinuing their .22 conversion units.
Tanfoglio Stock,or whatever it's being called these days. It's Tanfoglios answer to the CZ SP01.
Open Division is dominated by STIs. If you can't afford an STI Standard gun, forget about an Open gun. You also need to reload .38 super if you are going Open, as factory ammo will not make major powerfactor.
My advice is try before you buy. Go to a club match as a spectator, help patch targets and collect brass and ask if you can try out some guns. Helpers at matchs are always valued and most shooters love to show off their guns.
If you can't try before you buy then the CZ, Tanfoglio or Glock would be my picks.