I get asked quite frequently what the difference is between the screens we use versus the screens you can buy from eBay. The following post explains the quite subtle but very important differences.
The photo below shows the screen we use on the left and a screen you can buy on eBay on the right.

Above: Left: Bournemouth iPhone Repairs supplied screen. Right: eBay iPhone 4S Screen
The photo below shows the extra two adhesive pads added to the LCD and touchscreen connectors as fitted by Apple. These extra pads ensure that the two connectors are electrically grounded and the LCD displays a crisp picture. When the metal retaining clip is fitted, which also doubles as the wireless antenna, that the correct pressure is applied keeping them fully seated even after being dropped. Also added to the LCD screen is a new 3 piece speaker mesh assembly rather than having to reuse the existing mesh, like other repairers.

Above: A picture of an iPhone 4S screen supplied by Bournemouth iPhone Repairs
The eBay iPhone 4S screen comes supplied with no conductive pads on the touchscreen and LCD connectors. Also no speaker mesh.

Above: A picture of an iPhone 4S bought from eBay.
The photo below shows our supplied screen, it includes a UV filter and foam gasket over the proximity sensor window, the 3 piece speaker mesh fitted and a new adhesive ring around the camera lens holder.

Above: A picture of an iPhone 4S screen supplied by Bournemouth iPhone Repairs
The eBay iPhone 4S screen comes supplied with no speaker mesh, no UV light filter or foam gasket around the proximity sensor window and no ways of securing the camera lense assembly. Without the UV light filter and foam gasket the display wont turn off when you raise the phone to your face. This will generally mean you'll press the end call, mute or hold button with your cheak. Very annoying!!

Above: A picture of an iPhone 4S bought from eBay.
A customer bought his iPhone 4S with a broken touchscreen in today.

60 minutes later he collected his phone very happy that it looked and worked like new.

Just need to set the time and its finished.
A customer phoned up today and confessed to a DIY earpiece repair. He had dropped his iPhone 4S and the earpiece speaker had stopped working. After attempting a repair himself, he was left with a phone with a non working LCD screen, although he had successfully repaired his earpiece speaker!
After a bit of investigation, it looked as though the LCD ribbon was damaged, which meant the whole LCD/Touchscreen unit would need replacing.
The phone arrived in bits, with a few screws missing.
After a new LCD was fitted, a full 30point test was completed the phone was as good as new.
The customer was charged £65 for a new touchscreen fitted, a rubber grommet and 3 screws.
He went away very happy.
A customer brought her daughters iPod Touch in a few days ago for a screen replacement. It had been smashed for a while and the screen was being held together with sticky tape.
Above: Apple iPod Tough 4th Generation with smashed touchscreen.
Unfortunately we didn't have a white touchscreen in stock. The part was ordered the same day and turned up 2 days later. Once fitted the iPod Touch was as good as new.
Above: Apple iPod Tough 4th Generation with replacement touchscreen fitted.
The customer was charged just £50 and went away very happy!