Convenience is certainly important. If you don't carry it, you won't shoot it, and it's not worth it.
I totally agree with the wide angle thing kinda sucking... I shoot WAY more wide angle than I do telephoto, and 18mm wasn't quite doing it for me, so I ended up getting a Tokina 12-24 that I probably use 75% of the time.
If you haven't decided where to order from, I can highly recommend B&H Photo. Their customer service is outstanding. I bought a lens from them back in July, and it dropped in price $200 three weeks after I bought it. I called them up, and they credited my card back, and were really friendly on the phone. That kind of thing goes a long way in my book.
2004 UZJ100 - stockish for the time being.
Jetta Sportwagen TDI
Sold - 2010 Tacoma, lifted, locked, armored