Better amp or better tubes?


With this lockdown I'm finding myself and I'm sure many others listening to music more often and with that my mind has gone into upgrade mode.
My amp is a rare Quickilver 300B that must be at least 25 years old using genalax gold lion  300b tubes.
Over a year ago I sent an email to Mike sanders asking him about suggesting upgrades to the unit and surprisingly he told me if the amp is working fine to just leave it alone. We ok then.
The genalax 300b are modest in price  costing about $300 a pair and have worked flawlessly. If I were to upgrade the tubes, what direction would you suggest? To be honest, I'm a bit apprehensive in spending a lot for tubes since they can fail at anytime. Am I being overly concerned?

So, do I upgrade the tubes or amp? Amp budget of under 4k.

Thanks


emil
From your post, it seems that you have decided that the tubes and/or the amp is what is causing your desire to upgrade.  I think you should look at your whole system.  I recall once going into a dealer absolutely convinced that I needed a better or more powerful amplifier, which he could have easily sold me.  But he demonstrated that upgrading the preamp gave me much more of what I thought a better amp would do.  Just something to think about in these troubled times.  
Hi Chayro
Recently done just that. Sold my LTA Microzotl2 for the LTA Preamplifier. VERY happy with that move.
So my attention has turned to the amp.

Troubled times indeed. We all need a distraction



I would test the tubes to see what condition they are in. Its not surprising to find that a good quality 300b has lasted 25 years; they lasted over 50 years in the intercontinental telephone trunk lines which went from the US to Europe under the sea.  But the other tubes in the amp might bear taking a look-see.