I'll add my weight to the TM over the WE. WE's are cheap, and look nice. But they have severe quality issues. They have a bad tendency to rip themselves to pieces. This is most frequently seen in their 1911's. I haven't heard anything specific to their hicappa's but it's a good bet that they have similar problems. As far as pistols go, you can't do better then a TM hicappa. If you're planning to use a pistol as a primary then I wouldn't recommend anything but. They're accurate, reliable and have a huge amount of addons and upgrades available for them.
Something that concerns alot of people when it comes to pistols is full metal or not. ABS is more efficient, and all the higher quality manufacturers tend to only produce in ABS. For those that only want a pistol as a sidearm, well full metal just looks and feels so much nicer, generally better kick as well, but for a primary staying ABS is generally better. The downsides to full metal are they use more gas to move the heavier slide (this is particularly a concern in singlestack guns like the 1911) and generally cause more wear on the parts. Also, because of the heavier kick, the accuracy goes down, especially in rapid fire.
Upgrading the higher quality abs guns to full metal is possible but very expensive. It usually easily doubles the cost of the weapon if not more. There's a couple of guys who sometimes build and sell upgraded pistols, frequently in full metal. But you're looking at a price tag of $700-$1300.
If you're planing on using your pistol frequently as a primary then go with the TM hicapa. That said, as others have already mentioned, using a pistol as a primary, especially outdoors, is not advised. AEG rifles have better range, better accuracy, higher ammo capacity and are full auto. Unless you're very good a sneaking around you're going to get slaughtered. Another thing that's been mentioned, is if you're going to run a pistol as a primary, you're going to need a lot of mags, and those aren't cheap. At the minimum you'll probably want at least five mags. At $40-$50 a pop that's doubling your cost.