Mick,
I have a Record CL4, which is effectively what your CL3 would become if you fit a variable speed kit. It is a nice lathe to use, and I have turned pieces up to 24" in diameter by 3" thick with no problems whatsoever (other than lifting them on in the first place!!!) :roll:
My previous lathe was a 5 speed belt change job, and I find the variable speed to be a huge benefit. It makes the whole turning experience much more pleasurable.
It is particularly useful when turning off-balance items, as you can play around with the speed to find the optimum to reduce vibration, and then as you get the work piece more balanced, you can up the speed accordingly.
IMHO, if you can afford the upgrade, you won't regret it.
I agree with Chas's comments about the variable speed unit on the CL4 being in a bit of a dopey place, but I would guess that if you are upgrading, than you could mount the control box more or less where you like.
FWIW, there are other companies making a variable speed kit that will fit the CL3 which may be cheaper than buying the Record one - try doing a Google search, but Speed Genie is one that springs to mind.
Good luck with whichever option you decide to take.
Regards
Gary
Edit - PS - Welcome to the forum!!!