8" dob upgrade questions

I bought a DSO 8" dob from Anttler Optics this week and have to say I am very impressed with the scope for especially for what it costs. Has anyone tried any of the following from http://astronomy-shoppe.com/? primary or secondary collimation knobs, azimuth lock and tension knobs.

I also would like to be able to use my binoviewer and has anyone come up with a good conterweight? Thanks.

Dave

p.s. I probably could have saved myself a lot of money if I had bought this as my first scope and it might have been all I ever needed.

I wanted to mention that the Anttler version of the 8" dob has some very nice upgrades at a good price.
It came with a 2 speed focuser, roller bearings, 8x50 right angle finder and a fan.

Dave Adams