Just wanna know what you guys think is the right balance for sparring. I normally spar about 4-8 rounds twice a week (body sparring) and maybe 10 rounds head sparring once/twice a week (although to be fair this is normally only done for a few months at a time just to get out of bad habits from body sparring, ie keeping your hands low and then we go back to body sparring).

What do you think is too much/too little sparring?

Depends on the individual, experience level, pro or amateur, and when your next fight or season goal is.
At my club (in Denmark, Europe), the goal isn't going pro, but getting to the olympics, so we train specifically for that style. This means we do a lot of light sparring, for technique, feints and speed. Also, we do a lot of rounds without gloves, where you basically just tap the other guy. Mostly during the basic training cycle, though.
At one time we did 8 rounds of tough sparring, 4 nights a week the entire season. Needless to say, that got us nowhere. The fighters got burned out, and they just kept repeating the same mistakes over and over. You have to do drills to get the right movement patterns, instead of just sparring and hoping you'll pick it up along the way. Drills, drills, drills, and THEN sparring to put it together works much better, in my experience. :)

Is training with drills common in most gyms? Seems like a good way to train. When we do head sparring the coach tends to stop us regularly to correct mistakes but other than that we don't do any drills.

What kind of mistakes you talkin about, basic ones like punching technique/footwork, or more complex ones like strategy, fighting on the inside etc?

Just interested to know if I'm suffering from doing straight sparring

Is training with drills common in most gyms? Seems like a good way to train. When we do head sparring the coach tends to stop us regularly to correct mistakes but other than that we don't do any drills.

What kind of mistakes you talkin about, basic ones like punching technique/footwork, or more complex ones like strategy, fighting on the inside etc?

Just interested to know if I'm suffering from doing straight sparring

When I fought in the States, we didn't do drills, just mitts and sparring, so I don't know.
Here in Denamrk, it's not so common either, but in the eastern countries, they do it a lot, and look at the succes of their style, in the amateurs. So that's why we do it. The pro style won't win you amateur fights at an international level, that's why American fighters don't do so well anymore, but they make up for that when they turn pro. :)
The kind of drills I'm talking about are everything from feints, to combinations and slipping punches, even footwork (it's all connected you know). For instance, if you do drills of slipping punches, you won't make the common mistake of pulling back from punches once you get to sparring.
I think you'll be okay the way you're going, if your trainer is knowledgeable, and helping you out alot during the sparring. Especially if you're sparring in a way that'll allow you to try things out without getting punished by the other guy.

about 4 days a week...

round twice a week
from 3 to 6 rounds

When I fought in the States, we didn't do drills, just mitts and sparring, so I don't know.
Here in Denamrk, it's not so common either, but in the eastern countries, they do it a lot, and look at the succes of their style, in the amateurs. So that's why we do it. The pro style won't win you amateur fights at an international level, that's why American fighters don't do so well anymore, but they make up for that when they turn pro.
The kind of drills I'm talking about are everything from feints, to combinations and slipping punches, even footwork (it's all connected you know). For instance, if you do drills of slipping punches, you won't make the common mistake of pulling back from punches once you get to sparring.
I think you'll be okay the way you're going, if your trainer is knowledgeable, and helping you out alot during the sparring. Especially if you're sparring in a way that'll allow you to try things out without getting punished by the other guy.

Sounds good PD. It makes sense. To be honest I was planning to do some private training with a friend to work on defensive drills but considering what your saying I might do some other drills and then try and transfer it to sparring

i spar about 4 times a week, usually 3-4 rounds. the first round is normally bodywork.