First workout on my new routine

Upper body/arms

Before I did mostly machines, today I only used one (rear row).  I feel pretty good about it. 

3 things.  Do biceps and tri's take longer to move the weight up?  Took me 3 workouts at 50lbs of tricep pull down to reach 60lb.  I did 60lb at 3 set 6-8 rep for the last 3 workouts.  Is this a plateau or are they slow developing?  Same thing with biceps, but not as drastic.  Those are the only isolations I do for those muscles.  Maybe I'm not working them hard enough?

Lasty, I did DB flys with free weights at 25lb each.  I did 3 set of 8.  That was close to my max weight, probably could have done 30lb but it was my first time. I didn't really feel it though.  At the end I just wanted to try the cable flys, I felt those more.  Are the cable flys about as good as DB flys?

To answer your first question, you can expect slower increases in weight for the smaller muscle group, which is to be expected really. I bench press an extra 2-3 kilos every 2 weeks, but my bb curl increases are far lower.

Secondly, I would definitely recommend DB flys over cable flys. You use a lot more stabilizing muscles using DBs. The reason you wern't feeling it was most likely due to the fact that you are used to machines and havnt got the technique down. Watch scooby's vids on DB flys to see proper technique and if your still having trouble ask a buddy to make sure your sticking to good form.

When you say your wern't "feeling it" what do you mean by this? The reason i ask is i feel DB flys are a pretty essential chest exercise and it would be a pity if you left them out.