For lathe change wheels, just buy the cheapest option. 15 quid a cutter soon buys a 22mm arbor!
As Andrew, if you need real precision. Making your own you could cut for the true DP or MOD tooth count – remembering that the sets of 8 cutters are actually only supposedly accurate for the minimum tooth count for each cutter.
I suspect the RDG items are much like some of the ones offered from China, but at an elevated cost. There may, or may not, be some extra quality control checks on UK-sourced chinese items.
I bought a set of 8 cutters from China for about £55. Cheap and cheerful, but do be careful that you get what you expect – 14 1/2 or 20 degree PA (some pics, for 14 1/2 degree sets actually use a 20 degree pic). Supplied by ‘bang good’ would likely be the bottom of the pile, regarding quality, so I would avoid them (no quality control and worse than useless customer service).
Edited By not done it yet on 14/02/2019 11:27:42