Joined: Jan 2010
Posts: 9,831
Likes: 1,809
From: Northern California
Bikes: Cheltenham-Pedersen racer, Boulder F/S Paris-Roubaix, Varsity racer, '52 Christophe, '62 Continental, '92 Merckx, '75 Limongi, '76 Presto, '72 Gitane SC, '71 Schwinn SS, etc.
Looking at what's actually available in an 8-speed version, you'll find 12-32 and 11-32t. The Sunrace 11-32t has a rather big jump from 15-18t that I wouldn't want myself.
Sram and Shimano offer 12-32t in 8-speed, with only a 18-21t jump where the 3-tooth progression starts.
Since the 48t ring won't eliminate the need for a longer chain, I would consider that merely an option, and likely to cost at least $30.
I recommend buying the X-grade KMC chain, far better than their Z-series chain for just a few dollars more.