Who can recommend a good Freon A/C electronic leak detector?

I have three cars with A/C and it seems either one or the other is always needing an A/C recharge. Time to bite the bullet and purchase my very own 134A leak detector. I see a brand "Robinair" on Amazon, but I thought I better check with the guys (general term for both boys and girls) to see what experience others have had with the Robinair and any other brands. For a little over a hundred bucks, I think it would be worth it. Thank you.