+1 on the Magma. The Freakshow is another decent one I liked but unlike the Magma does have leakage issues due to it's air-flow design.
A Mutation design is another I have heard great things about but no 1st-hand experience.
Currently 40 pounds is about $62 U.S. which should get you close to a nice Clone of Higher-End Authentic even with shipping.
I just got a 13 Heavens & 9 Hells made by CompVape here in the States. Impressive to say the least and just Aces All around. Probably for a tad more Pounds Sterling you could get one of those or something similar which would definitely return Value beyond the Investment rendered.
If that might foot the Bill or be worth checking out to you, you can see it and other similar Home-Brewed RDAs and quality Clones and such at:
13 Heavens 9 Hells RDA by Compvape In Stock - RBA Vapor Store
Of course you can also do some good research and Market comparable Study on eBay. Just highly recommend being careful to get a good Quality Brand Clone such as Infinite. Just my experience from some regrettable Lessons while becoming "schooled" by the University of Hard Knocks so to speak.
ECF and the Members here helped a TON on preventing those later after my misspent Vape-Youth and wish I had found it quicker.
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