I’ve not had a play with the CT axes, but there’s a whole lot more going on with Quarks. As has been said, you can fiddle around with picks, hammers, adzes etc (may not be important to you). You’ve also got a whole lot more options for leashes – it doesn’t look like you could use clippers or bungees with the CTs. Again, this might not bother you. The ‘gripping area’ of the shaft is more shaped on an axe like a Quark – which I’d personally a lot more comfortable that the CT’s straight handle section. If you’re going leashless, this might be a consideration.
With cheaper axes you’re also potentially getting picks that aren’t quite as tough, so you might find yourself sharpening or replacing them. Not having seen them, the picks on the CTs might be fine, and that might not bother you anyway.
In short, they look fine, but it really depends on what you want to do and what they feel like to you. Another cheap option would be something like the tried and tested DMM Fly or one of the Grivels (I’d go with the latter). (If you want cheap and leashless, check out the Monsters.) Or look for something second hand.
Personally, I use BD Vipers, which are amazing, and orange. Well worth a look if you’re considering Quarks. Axes can make a massive difference to how comfortable and relaxed you are on a climb (although not on most easier Scottish routes – more so if you’re messing around dry-tooling!), so find some you’re happy with.
Getting ridiculously excited about winter now…