I am not a user of retra strobes however having had several discussions with them I think it is commendable that they continue to bring innovation out.
I also think it is understandable that older model are being discontiuned once stock is sold out as long as they honour the warranty this is nothing strange
Like anything a consumer needs to decide if the new features are worth a change bearing in mind that offloading their now discontinued item can be costly but nothing lasts forever.
I tend to keep my strobes for at least 5 years I do not use them enough to justify changing them quicker and for cameras in my underwater housing this is at least 3 years but usually more like 5
Any time I buy something I do a lot of research to be sure I am happy with the limitations and trade off of what I got and then simply ignore new products coming out. However I also recognise that if I bought a product that did not fit the bill I would be looking for a change much quicker. It has not happened yet though