DeVere 504 bulb: EJL or ELC?

[polyglot]

I recently scored a 504 (head pictured here with covers up if the version matters) and have it all working nicely. Figured I'd buy some spare bulbs since they have such a short rated life.

All my googling says that these are meant to have an ELC (24V 250W 3400K) bulb whereas mine has an EJL (same but 200W) installed. Can I just assume this was a previous owner being cheap/lazy or was there ever a version that used an EJL?

[Shen45]

I have the 250 watt version in mine. Ring PJ White as they carry them and if memory serves me they have a long life version for not much more cost.

[polyglot]

Do the "long life" ones actually last any longer in enlarger use? My understanding was that they had a more-refined halogen-cycle that reduces filament evaporation in continuous use, whereas in an enlarger it's going to be thermal stress from the frequent switching that kills it.

I'll see what PJ's have to say, otherwise they're pretty affordable ($31 shipped for 3 GE or Osram; cheaper for generic) on eBay.

[Shen45]

Mine have lasted a very long time and I'm a continual switch on switch off printer. Mine has been in the enlarger for at least 4 years now. A friend uses normal globes but has replaced 3 or 4 in that time and we use our enlargers a similar amount. If you can get a reliable supply of globes just stock up, they do seem to last a reasonable amount of time.