Good to hear your modded 45 is doing it's job, I had a modded 3500 & I liked it because I had control over the gain, the best coil for it was the Detech 11" spiral... just turn the gain down a little and away you go, it was very sensitive to tiny bits. Very quite and stable at the same time. One thing I will ad is my 3500 handled EMI better then my 5K which pissed me off to be honest. Ok back to modded 45's... I met a couple up at Kondoparinga Station who had a modded 45 done in VIC & it was a disaster, it couldn't be used unless it was in enhance. Not sure what was wrong with it but old mate was very disappointed to say the least. I believe it was going back to be fixed for a 2nd time!!. I love my 5K & in my opinion it doesn't need modding at all, especially when it consistently finds gold. Only upgrade now is a 6K or a good 2nd hand Zed. I find way more little nuggets then bigger bits.. so the 6K is looking pretty good right now.