No experience of LD. I used to have an entry-level Trantec system (transmitter and 2 receivers), and that cost (IIRC) £440 in 2002. I imagine prices have come down since then as they have become more popular and other brands have entered the market, so the low price doesn't necessarily mean it's poor quality.
A couple of things to be aware of -
- If you share your setup with the singer, then you will have the same monitor mix.
- Make sure the radio frequency range isn't about to be sold off to taxis, 4G or whatever.
- The Trantec earphones were shocking. At the price point you are looking at, I would expect them to be 'functional' at best.
- If/when you upgrade your earphones, bear in mind that isolation is a two-edged sword - yes you are saving your hearing, but the instruments that don't go through the PA will only be audible as 'spill' through your vocal mics.
Even so, I would definitely recommend IEMs over wedge monitors. They are smaller and lighter, the audio quality is usually better, and they keep down the on-stage volume and reduce 'volume wars'.