Jap. Maples don't have any more of a vulnerability to pest than any other tree. If you will be planting it in a full sun location that defiantly needs to be kept in mind as most japanese maples do not fare well in full sun exposure. That being said Fire glow and blood good are great candidates for full sun, Fire Glow is more showy than Bloodgood and better in my opinion. Emperor again needs partial shade during the hottest period of the day and will not be suitable for full sun.

As for how large they will get, that will be the least troublesome issue as you can keep them to just about any size and height that you desire through yearly pruning. That being said I would still give them adequate space from a wall to give them good light and air circulation as well as keeping in mid the aspect of aesthetical appeal. Since I don't know your exact predicament of the planting location in question I cant say exactly how far it should be placed from the house wall.

If you would like I can send you a few online Japanese Maple nursery sites where you can browse through there inventory and look for some Full sun tolerant verities that you might like. Just send me a personal message so i will be notified through my email since I don't frequent this site too much as of lately.

Hope this helps.
-Mike

I have a somewhat different opinion :-) ALL red leafed J. maples are moderate to very sun tolerant, so any of the listed selections would work -- all 3 are recommended for both hot climate and full sun locations (SoCal, Texas, southeast). 'Bloodgood' tends to lose some coloring or 'green out' in full sun - the other two tend not to.

There is minimal difference between the three - 'Fireglow' has a slightly different coloring (less deep purple in season; more of a dark red) and 'Emperor I' is later to leaf out than 'Bloodgood' so better in locations that may experience late spring frosts and is slightly smaller when mature. All three will produce a rounded canopy but not necessarily an evenly rounded canopy :-)

According to Vertree's, 'Bloodgood' will mature at around 30-35' with an equal spread, Emperor I will be slightly smaller (25-30') and 'Fireglow' at 18-20' with a narrower spread. If planting close to a house or other structure, you want to keep at least half the distance of the mature spread, so no closer than about 17' for the BG, 15' for the Emp and 10' for 'Fireglow'.