IMO the best UL RGs are 100 credit 9 hole ones for several reasons:
- uneven lies are tough and require a lot of concentration (and calculation), therefore 18 holes are a bit tiring
- 50 credits for 9 holes or 100 for 18 don't make sense considering ball costs - only the first 3-4 actually win credits (and it doesn't make sense from a competition viewpoint to use cheap balls)
- for some reason (unknown to me) many people are scared of UL and thus unwilling to risk a lot of money on it
It's sad however that for the last few months such UL RGs were missing...