I have one gripe about the Suzuki 2005 GS500F it's build quality. You have to be prepared to keep this bike sprayed with anti-corrosion spray on all the vulnerable parts (you'll find out which they are if you keep an eye on them and watch for corrosion to appear - then give them a squirt regularly and you'll be OK). This is especially important in the (English) winter when they salt the roads. If you're not careful your bike will look like a real dog by the end of the winter. Regarding after-market exhausts for the GS500F, in the UK try Predator (Google it and you'll find it easy enough) they do a nice stainless exhaust for around £300 which should see you all right for many years (better than the mild steel job that Suzuki put on which is never going to last any time at all).
Specifications:
Engine: 487cc, four-stroke, twin cylinder, air-cooled, DOHC
Bore Stroke: 74.0 x 56.6mm
Compression Ratio: 9.0:1
Fuel System: Mikuni BSR34SS
Lubrication: Wet Sump
Ignition: Digital/Transistorized
Transmission: 6-speed
Final Drive: #520 chain
Overall Length: 2080mm (81.9 in.)
Overall Width: 800mm (31.5 in.)
Overall Height: 1150mm (45.3 in.)
Seat Height: 790mm (31.1 in.)
Ground Clearance: 120mm (4.7 in.)
Wheelbase: 1405mm (55.3 in.)
Dry Weight: 180kg (396.8 lbs.)
Suspension Front: Telescopic, oil damped
Suspension Rear: Link type, 5-way adjustable preload
Brakes Front: Single hydraulic disc
Brakes Rear: Single hydraulic disc
Tires Front: 110/70-17
Tires Rear: 130/70-17
Fuel Tank Capacity: 20.0 liter (5.3 gal.) 19.0 liter (5.0 gal.) CA. Model
Color: Blue/White, Black/Silver
Specifications:
Engine: 487cc, four-stroke, twin cylinder, air-cooled, DOHC
Bore Stroke: 74.0 x 56.6mm
Compression Ratio: 9.0:1
Fuel System: Mikuni BSR34SS
Lubrication: Wet Sump
Ignition: Digital/Transistorized
Transmission: 6-speed
Final Drive: #520 chain
Overall Length: 2080mm (81.9 in.)
Overall Width: 800mm (31.5 in.)
Overall Height: 1150mm (45.3 in.)
Seat Height: 790mm (31.1 in.)
Ground Clearance: 120mm (4.7 in.)
Wheelbase: 1405mm (55.3 in.)
Dry Weight: 180kg (396.8 lbs.)
Suspension Front: Telescopic, oil damped
Suspension Rear: Link type, 5-way adjustable preload
Brakes Front: Single hydraulic disc
Brakes Rear: Single hydraulic disc
Tires Front: 110/70-17
Tires Rear: 130/70-17
Fuel Tank Capacity: 20.0 liter (5.3 gal.) 19.0 liter (5.0 gal.) CA. Model
Color: Blue/White, Black/Silver