One of the enduring treats of transparency is seeing each vibrant image come to life on the lightbox. There is nothing like it.
I have shot 35mm Velvia and some Provia almost exclusively since I think 1994. Over that long period of time many, many images were taken to the Ilfochrome Classic media and framed. The discontinuance of that means these musuem-grade conservation framed prints are now appreciating in value.
In September last year I migrated to the 6x7 format which is used for the majority work now, but due to that format's size and weight specs, the evergreen, versatile 35mm EOS 1N (loaded with Velvia, Provia or even a B&W like ACROS) is the preferred choice for bushwalking (also multiformat pinhole).
No trouble finding E6 processing at the moment; they do the processing, I bring it back to the studio for cutting and vetting. The best of the pics are archival card mounted and labelled; this assists the printer as it has all my identification info on it, additional to scanning, colourimetric and final RIP requirements.
I do have a cache of Velvia, Provia and the much-derided Velvia 100F and only place an order for more film when there is one box remaining.