I have the Ionics pro5 600lt which is probably the most expensive but what I can gather it is the best! I bought it 2.5 years ago and (touchwood) I havent had any problems and would buy another. Your budget is 3.5K but their pro5 600lt is £4115 plus VAT but they do a deal for £144.02 over 3 years, so that works out at £5184.72. Lots of money but if you can afford £144+VAT a month its worth it.
You will get a lot of negative (and positive) feedback from other posters on this site about Ionics because of the price but I do think the aftersales support, reliability, and the security that the equipment has been crash tested in a van is worth alot. (Insurance companies are beginning to ask for Ionics standard of crash testing before they will insure you).
I wouldnt buy their poles though....They are very expensive and Gardinerpolesystems.co.uk are much better for poles and accessories. Also, Alex Gardiner (The daddy of wfp!) is regularly on this site answering queries.
By the way, I dont work for Ionics, just a very happy customer. Fel free to contact me on
info@ro-sheen.co.uk if you want anymore info.....
PS: Welcome to this site!