The ball movement on the 33NS was not as smooth as the Q3T, and I took care to optimize friction on both ballheads for the same camera, a Fuji S5 Pro. It was quite noticeable, but may be less noticeable with the 36N. As you can see from the attached picture below there is a big difference in the ball size and this was a major factor in the feel of the ballhead when you're orienting the camera. Also the friction control on the 33NS had a shorter throw than on the Q3T so setting the friction was a bit more fiddly. Both of the panning locks worked fine, but the function on the Q3T is not a lock, it's actually a brake which does bother some people. For me it works fine.
I think the Q3T is better designed/engineered than the 33NS. When you have a travel tripod with the legs folding back parallel to the center column, you need a ballhead with a maximum outside diameter of <=50mm for both the panning base and the ball housing. Both the Q3T and the 33NS have a panning base with a 50mm diameter. However Markins have managed to fit a 38mm ball inside their housing but the best that Photo Clam could achieve is 33mm. The Q3T has been around for quite a while but apparently Photo Clam have been unable to match or exceed its spec. Moving to the 36N it has a panning base of 53.5mm yet only has a ball diameter size of 36mm, still smaller than the Q3T. However that panning base diameter means that most tripod legs won't fold back parallel to the center column, which can make for an awkward package. This may or may not be an issue for you but most people buy a travel tripod for size and convenience and sacrifice some stability to get those features.
Fit and finish on the Photo Clam is very good and indistinguishable (to my eye) from the Markins. Both are excellent.
One last thing about the Photo Clam and you may have an entirely different preference for this. The way I like to use my ballheads is to have the drop slot at the front facing the subject, the ball locking knob on the left and the panning lock at the back, facing me. All of my ballheads from different manufacturers have this layout. If I use the Photo Clam with the ball locking knob on the left the drop slot is on the right and that's no good for me. YMMV though.
I approached the tripod problem differently and use one tripod for when I am not going to be going far from my car and another one for hiking. The hiking one requires more care in its use and has a 8 lb. limit for the ball head but is very lightweight and compact. Getting two tripods for each use was a lot cheaper than buying one super strong and light setup.
I recently saw a product release about the Oben CT-3400 and it looks great at $350 with support for up to 12.4 lbs. and weighing a total of 2.9 lbs. with its ball head and collapsing down to 15 inches in length. It may be time to get another tripod.
