Starting tomorrow, I hope to start 10m WSPRing at 10mW ERP.
Clearly, my previous attempts using 500uW work when conditions are very good, but 10mW ERP will be a good indication of how 10mW ERP (licence free under UK 8m ISM rules) 8m might behave. An extra 13dB could make a real difference. If I get spots on 10m WSPR, I may not bother to renew my 8m TX permit as I will learn more experimenting for free with 8m 10mW ERP WSPR. I shall probably use 8M3ISM on 8m WSPR.
Judging by reports today, several spots might have been managed with 10mW ERP on 10m.