,recently ive bought 2 gravel vacs that are battery powered in the last 4 month,both have lasted no longer than 6-8 weeks,they were only the cheap £10 ones so werent so expensive,but if they going at a ratio of 6/8weeks this is no good,does any no of any decent ones on the market that are reliable(manual sphion no good),and are the pump powered ones any good?